Video: base lockup and cleaning
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• Locking up your base in a platen press •
• Locking up your base in a Heidelberg Windmill •
For cylinder presses
First, familiarize yourself with your press’s manual (you might find our collection of press manuals useful).Small bases can work in cylinder presses, but there is no disadvantage to maxing out the press bed/chase with a large base. If you’re trying to max out the printable area of your press, the only thing else that needs to fit in the bed/chase are quoins, to hold the base against the rails. But in most cases, you’ll need quoins, as well as furniture, reglets, and or leading to fill up the space around your base and quoins. Tighten the quoins somewhat loosely so that the base doesn’t buckle up. Make sure that the base is completely behind the “dead line” inscribed at the head of the bed. If your base is over this line, the grippers may impact the base and dent the base.
For platen presses other than Heidelberg Windmills (i.e. C&P’s, etc.)
We recommend a thorough reading of one or more of the following books:
- Cleeton & Pitkin’s General Printing
- Polk’s The Practice of Printing
- Mill’s Platen Press Operation
In the chase, you’ll need to fit your base, the quoins, and any furniture, reglets and/or leading to lock the base in place. On an imposing stone, lock up the base, tightening the quoins enough so the base won’t slip out when you carry it to the press.
Most platen presses, other than the Heidelberg Windmill below, use gauge pins to hold the press sheet in place for printing. If these pins holding your paper hit the base when printing, then they’ll smash and damage your base. For this reason, it’s important to make sure you’ve purchased a base that’s small enough to accommodate the gauge pins. Most gauge pins measure about an inch long, and to give you some flexibility in positioning them, we recommend a base that’s 1.5” smaller in width and length than the inside dimensions of your base.
After you’ve locked up your base and put the chase in the press, position your gauge pins in a spot that won’t impact the base during printing. To make sure that the gauge pins don’t hit the base, turn the press over slowly by hand on impression while peering in the mouth of your press. You’ll be able to see if there is impact between gauge pins and base and then you can adjust the gauge pins accordingly.
If you want to run with grippers, you’ll need to make sure they’re far enough of the outside of the base that they won’t impact your base when the press closes. If the grippers can not remove the press sheet from the form after printing in this position, make a frisket out of string or paper between the two grippers. Make sure that the string or paper that you tie between the two gripper arms doesn’t get between the surface of your printing plate and your press sheet. This frisket will help remove your sheet from the form and mask out any non-printing areas of the plate that might be inking up.
for Heidelberg Windmills
We recommend a thorough reading of one or more of the following books:
- Cleeton & Pitkin’s General Printing
- Polk’s The Practice of Printing
- Mill’s Platen Press Operation
In the chase, you’ll need to fit your base, the quoins, and any furniture, reglets and/or leading to lock the base in place. On an imposing stone, lock up the base, tightening the quoins enough so the base won’t slip out when you carry it to the press.
Whether you’re using gripper register or lay gauges, you can put the base right up to two adjacent edges of the chase. Keep in mind that paper-clip-like lay gauge pins may hit the bottom edge of the base when printing. A way to keep this from marking your press sheet (or impacting your base) is to cut out the packing beneath where the pin hits.
We don’t recommend running with a frisket attachment unless you have a very small base (small enough to position off to the side of the frisket arms). Otherwise, the frisket arms will dent the surface of the base.